无法使用自定义链接器文件在 STM32L476 上编辑具有 .noinit 属性的整数

发布于 2025-01-12 00:36:37 字数 1022 浏览 5 评论 0原文

我正在第一次尝试使用链接器文件。最后我想要一个变量在重置后保持其值。我正在使用 STM32L476。

为了实现此目的，我修改了链接器文件：STM32L476JGYX_FLASH.ld 和 STM32L476JGYX_RAM.ld 以包含名为 NOINT 的分区。

MEMORY
{
  RAM    (xrw)    : ORIGIN = 0x20000000,   LENGTH = 96K
  RAM2    (xrw)    : ORIGIN = 0x10000000,   LENGTH = 32K
  FLASH    (rx)    : ORIGIN = 0x8000000,   LENGTH = 1024K -0x100 
  NOINIT (rwx)     : ORIGIN = 0x8000000 + 1024K - 0x100, LENGTH = 0x100
}


/* Sections */
SECTIONS
{
...
 
     /* Global data not cleared after reset.  */
    .noinit (NOLOAD): {
        KEEP(*(*.noinit*))
    } > NOINIT
...

在main.ci中将变量reset_count初始化为全局变量。

__attribute__((section(".noinit")))  volatile uint32_t reset_count = 0;

=0 部分只是为了简化。我实际上想在函数中的某处将 Reset_count 设置为零。

当我运行程序并逐步完成初始化时，我希望看到reset_count的值为0。但不知怎的，我总是得到0xFFFFFFFF。我似乎无法编辑 Reset_count 变量。有人能告诉我如何使该变量可编辑吗？

原文

I'm doing my first attempt working with linker files. In the end i want to have a variable that keeps it's value after reset. I'm working with an STM32L476.

To achieve this i modified the Linker files: STM32L476JGYX_FLASH.ld and STM32L476JGYX_RAM.ld to include a partition called NOINT.

MEMORY
{
  RAM    (xrw)    : ORIGIN = 0x20000000,   LENGTH = 96K
  RAM2    (xrw)    : ORIGIN = 0x10000000,   LENGTH = 32K
  FLASH    (rx)    : ORIGIN = 0x8000000,   LENGTH = 1024K -0x100 
  NOINIT (rwx)     : ORIGIN = 0x8000000 + 1024K - 0x100, LENGTH = 0x100
}


/* Sections */
SECTIONS
{
...
 
     /* Global data not cleared after reset.  */
    .noinit (NOLOAD): {
        KEEP(*(*.noinit*))
    } > NOINIT
...

In the main.c i initialize the variable reset_count as a global variable.

__attribute__((section(".noinit")))  volatile uint32_t reset_count = 0;

The =0 part is just for simplification. I actually want to set reset_count to zero somewhere in a function.

When i run the program and step through the initialization i would expect to see the value of reset_count as 0. But somehow i always get 0xFFFFFFFF. It seems like i can't edit the reset_count variable. Can anybody tell me how i can make this variable editable?

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

旧故 2025-01-19 00:36:37

从这个问题中尚不清楚您是否想要一个在断电时保持其值的变量，或者只是在电源保持打开但硬件复位脉冲时保持其值。

如果您想要在断电时保持其值的东西，那么您的链接器脚本可以将该块放入闪存中，但您需要使用函数HAL_FLASH_Program等来写入它，您不能只做任务。此外，您可以简化链接器脚本，只需放置 >FLASH，而不是创建 NOINIT 输出区域。

如果您想要一个在电源保持开启时在复位过程中持续存在的变量，那么您需要将该变量放入 SRAM 而不是闪存中，例如如下所示：

.noinit (NOLOAD) :
{
    *(.noinit*)
}
> RAM2

请注意，您不需要使用 KEEP 除非您想要链接一个未引用的部分，如果您实际使用变量，则不会出现这种情况，并且您不需要紧接在 .noinit 之前另一个 * 除非您部分名称不以 a 开头.，他们应该这样做。

It is not clear from the question whether you want to have a variable that keeps its value when power is removed, or just while power stays on but hardware reset is pulsed.

If you want something that keeps its value when power is removed, then your linker script is ok to put the block in flash memory, but you need to use the functions HAL_FLASH_Program etc. to write to it, you can't just make an assignment. In addition, you could simplify the linker script by instead of creating the NOINIT output region, just putting >FLASH.

If you want a variable that just persists across reset wile power stays up then you need to put the variable into SRAM not FLASH, for example like this:

.noinit (NOLOAD) :
{
    *(.noinit*)
}
> RAM2

Note that you don't need to use KEEP unless you want to link a section that is unreferenced, which will not be the case if you actually use the variables, and you don't need another * immediately before .noinit unless you section names don't start with a ., which they should.

回复收藏 0 原文